Drafting appliance.



F. M. PRINTZ & A. FROST.

DRAPTING APPLIANGE.

AIPLIOATION rum) 23.15, 1909.

Patented Oct. 11, 1910.

QMEREIM UNITED STATES PATENT OFFICE.

FREDERICK M. PRIIITZ AND ANTON FROST, OF CHICAGO, ILLINOIS.

DRAFTING APPLIANCE.

To all whom it may concern:

Be it known that we, FREDERICK VI. PRINTZ and ANTON FRosT, a citizen ofthe United States, and a subject of the King of Norway, respectively,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Drafting Appliances, ofwhich the following is a specification.

The object of this invention is to provide means for holding the head ofa square in close contact with the working edge of a drawing board ortable and for frictionally holding a square from sliding along the boardor table except when moved by the operator.

In the accompanying drawings, Figure 1 is a perspective viewillustrating the practical use of an appliance embodying the features ofour invention. Fig. 2 is a fragmental section through the head of the T-square. Fig. 3 is a fragmental top plan view of said head. Figs. 4 and 5are fragmental views of a bracket entering into the construction of theappliance. Fig. 6 is a tragmental View of another bracket comprised inthe device.

For the purpose of illustrating our invention, we have shown it inconnection with a drawing table, although it will be understood that itmay be applied as well to a drawing board intended to be laid upon anysuitable table or desk.

In Fig. 1, A refers to the table top or board, B to a Tsquare, and B tothe head of said T-square. The head 13' is held in close contact withthe edge A of the table by means comprising a flexible, non-extensiblemember such as a wire 1 strained between two brackets 2 and 3 secured toopposite sides of the table, said brackets being of such form and solocated as not to be in the way of the operator. The wire 1 may besecured to the brackets 2 and 3 in any suitable way. e have herein shownone end of the wire as being passed through an eye 4 in the bracket 2and secured therein by means of a set screw 5. The other end of the wireis connected with a tension-adjusting screw 6 carried by the bracket 3.In this instance, the connection between the wire 1 and thetension-adjusting screw 6 is formed by passing the wire through an eye 7on said screw,

Specification of Letters Patent.

Application filed February 15, 1909.

Patented Oct. 11, 1910:

Serial No. 477,878.

the wire having a head or enlargement 8 thereon to prevent it frompassing through said eye.

Attached to the head B of the T-square at a suitable place, as, forexample, upon the upper side thereof, is a means against which the wire1 is arranged to bear. Said means, in this instance, consists of a plate9 screwed or otherwise rigidly secured to the head B, said platecarrying two grooved studs or buttons 10 over which the wire 1 extends.The eyes 4 and 7 and the buttons 10 are arranged so that said buttonsdeflect the wire 1 out of a straight line joining the eyes 4: and 7.

It will be seen that the pressure of the wire 1 upon the buttons 10 willcause the head B of the T-square to be held in close contact with theedge A of the drawing table or board, thereby insuring accuracy in theuse of the square and relieving the draftsman of the necessity ofattending to the position of the head B with relation to said edge. Thewire 1 also tends to tilt the T-square with the inner edge of the headas a pivot point, so as to hold the blade fiat in contact with the boardat all times. Furthermore, the pressure of the wire 1 upon the T-squareis suflicient to hold the latter against sliding along the board shouldthe latter be raised or tilted. The pressure of the wire 1, however, isnot suflicient to interfere with the free movement of the T-square alongthe board by the draftsman.

We would have it understood that we desire not to be limited to theprecise details of construction herein shown and described, for variousmodifications will occur to persons skilled in the art.

We claim as our invention:

The combination with a drawing board and a T-square, of a pair ofbracket-s having their bases secured to opposite edges of said boardadjacent one end thereof, said brackets being bent outwardly from saidbases to bring the outer ends of the brackets a suflicient distance fromthe board to provide a space for the head of said T-square when thelatter lies near the edge of the board; a grooved button on the upperside of said T- square head; a non-extensible flexible member secureddirectly to said brackets and strained directly between them along saidend of the board, said member engaging said carried by one of saidbrackets for adjustbutton and being bowed outwardly thereby ing thetension of said member.

to frictionally hold the head of the T-square FREDERICK M. PRINTZ.against the edge of the drawing board, the 1 ANTONFROST.

pressure of said member acting also to hold VVitnesses:

the blade of the T-squa-re into contact with 0. PAUL PARKER,

the upper surface of the board; and means GEORGE L. CHINDAHL.

